change native VLAN

[Turbo727]

Hi,

I have a closed REP ring with administration vlan 10. I am just wondering if I change native vlan from current default vlan 1 to a unused vlan, eg 2 and not permit vlan 2 on trunks will I lose the ring or cause any outage?

Thanks.

[Vivek Ganapathi]

I believe yes. You would loose your ring. Because REP sends LSL PDU's over the ring on the native VLAN. So, if you were to change the native VLAN & doesn't permit them over the ring, then i believe you would loose it.

Vivek.

[Turbo727]

Thanks Vivek,

I understand PDU is sent untagged. But we have REP admin VLAN which is not native VLAN. do I still require a native VLAN for PDU?

[Vivek Ganapathi]

This seems to be a good question, i will come back to you on this. Talking to a friend of mine who worked extensively on REP.

Vivek

[Vivek Ganapathi]

Alright, just got it checked from my friend. As per him, the admin VLAN is used for TC Notifications & BPA Advertisements. Being a closed loop ring topology you have, you are free to go ahead with changes to your native VLAN as all the communication happens over admin VLAN once you have them configured or else by default it would be VLAN 1.

But do ensure care while doing this, as there is no specific documentation showing this & specifiying this. Better to do this off-business hours or with a proper outage schedule.

Do let me know how you go with it as i m even curious about this.

Thanks

Vivek

[bunjiega]

my guess is if you have devices in vlan 1, then you would have connection issues until you made that change on all the switches in the layer 2 domain because whatever the native vlan is.. The packets are not tagged in that vlan.

Sent from Cisco Technical Support iPhone App

[Turbo727]

Thanks Jeremy. We have no device in VLAN 1. my concern is whether REP relies on untagged VLAN?